/*
 * Copyright (C) 2018 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.internal;

import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.List;
import javax.annotation.Nullable;
import okhttp3.Headers;
import okhttp3.internal.duplex.HeadersListener;

public final class RecordingHeadersListener implements HeadersListener {
  final ArrayDeque<Headers> receivedHeaders = new ArrayDeque<>();

  @Override public void onHeaders(Headers headers) {
    receivedHeaders.add(headers);
  }

  public @Nullable Headers takeFirst() {
    return receivedHeaders.poll();
  }

  public List<Headers> takeAll() {
    List<Headers> result = new ArrayList<>();
    for (Headers headers; (headers = receivedHeaders.poll()) != null; ) {
      result.add(headers);
    }
    return result;
  }
}
